Automatic spraying machine



Ap 1942' H. J. PATTISON I 381,9

AUTOMATIC SPRAYING' MACHINE Filed March 24, 1939 7 Shets-Sheet 1 INVZFVTOR ATTORNEY April 1942- H. J. PATTISON 2,281,169

AUTOMATIC, SPRAYING MACHINE Filed March 24, 1939 7 Sheets-Sheet 2 [NVENTOR BY/11rZ6rZ J 7 42 2 21501 gb ijwl W 3 A TTORNE Y5 V/ "11 ,4/ 1 miP 1942. H. J. PATTISON 2,281,169

AUTOMATIC SPRAYING MACHINE Filed March 24, 1959 '7 Sheets-Sheet :5

- IN VEN TOR Y He rierz J7 7522 2 2 mm 2 Qs ve a A TTORNE Y AUTOMATICSPRAYING MACHINE Filed March 24, 1939 7 Sheets-Sheet 4 IN VENTORZ/erieri J i dfzzt zz A rramvzaa April 28, 1942. H. .1. PATTISON2,281,169

- AUTOMATIC SPEAKING MACHINE Filed March 24, 1939 7 Sheets-Sheet 5INVENTOR A TTORNE April 28, 1942. H. J. PATTISON 2,281,169

AUTOMATIC SPRAYING MACHINE Filed March 24, 1939 7 Sheets-Sheet 6[NVENTOR A TTORNE EYS,

'7 Sheets-Sheet '7 H. J. PATTISON AUTOMATIC SPRAYING- MACH INE FiledMarch 24, 1939 [NVENTOR flerzarf J 7 4236215027.

ATTOR I I L April 28, 1942.

Patented Apr. 28, 1942 UNITED STATES. Y PATENT OFFICE AUTOMATIC SPBAYINGMACHINE.

Herbert J. Pattison, Detroit, Micln, asslgnor to Briggs ManufacturingCompany, Detroit,

Mich, a corporation of Michigan Application March 24, 1939, Serial No.263,954

12 Claims.

This invention relates to paint spraying machines or devices and moreparticularly to an improved automatic spraying machine adapted toperform a variety of spraying operations.

' Spraying installations having manually controlled stationary sprayguns and conveyor for moving the work past such guns have beensuccessfully used on large pieces such as automobile bodies, structuralsteel beams, large panels, and the like. However, installations of thischaracter cannot be used for painting small pieces, of odd shapes, suchas various frames, bent pieces of molding, and the like, withoutprohibitivelylarge waste of paint, space, and time. Therefore, sprayingof suchsmall pieces has been done by hand with resulting inefllciency,waste of time, material, and factory space. Such hand operations arealso injurious to the'health of the operators and give low volume ofproduction.

One of the objects of the present invention is to provide an improvedautomatic paint spray-- sumed to look in the direction of ing machinewhich can perform spraying operations on a variety of workpieces whichheretofore had to be sprayed by hand.

Another object of the invention is to provide an improved automaticspraying machine which can be used for spraying such workpieces as bentpieces of molding, automobile window frames, and the like, and isadapted to spray the paint only over the surface of the workpiece andnot on the conveyor, thereby eliminating the excessive waste of paint bypreventing wasteful spray-- ing of paint through the openings in theworkpieces onto conveyor surfaces.

A further object of the invention is to provide an improved sprayingmachine which is substantially continuous and automatic in its operationand can be served by one operator only and yet have a high productivityand give uniform coats of paint onthe workpieces.

A still further object of the invention is to prothe followingdescription and appended claims,

reference being had to the accompanyin drawings forming a part of thisspecification wherein like reference characters designate correspondingparts in the several views.

Fig. 1 is a perspective view of the automatic machine embodying thepresent invention, said machine being viewed from its delivery or finishend.

Fig.2 is a planview of a window frame or garnish molding which may bepainted dr sprayed in the automatic spraying machine of Fig.1.

3 is a sectional view taken in the direcon of the arrows on the sectionplane passing through the section line 33 of Fig. 2.

Fig. 4 is a perspective side view of the machine illustrated in Fig. 1,the observer being prethe arrows from the line l--l of Fig. 1. 1

Fig. 5 is a fragmentary perspective view illustrating the improvedautomatic spraying machine, the observer being presumed to look at saidmachine down from the right-hand upper corner thereof as indicated bythe arrow designated by the character "5 in the upper right-hand cornerof Fig. 1. a

Fig. 6 is a transverse vertical sectional view of the machine, said'view being taken in the direction ofthe arrows on the section planepassin through th line 6-45 of Fig. 4.

Fig. 7 is a view partly in section being presumed to look down from theplane passing through the me 1-4 of Fig. 4.

vide an improved spraying machine which 00- cuples very-little space andyet gives a large volume of production.

A further object of the invention is to provide an automatic sprayingmachine having improved means which automatically bring the movingworkpiece to a stop when it reaches a predetermined position, startsoperation of the spraying gummoves said gun around the work- Fig. 8 is aview illustrating solenoid means controlling the work conveyor switch,said view being taken in the direction of the'arrows on the section linepassing through the line 8-8 of Fig. 7.

Fig. 9 is a sectional view taken in the direction of the arrows on thesection plane passing through the line 9-4 of Fig. Tend illustrating thespray gun and the operative arrangement thereof.

Fig. 101s an electric wiring diagram illustrating the electric circuitoperating the improved automatic sprayingmachine embodying the presentinvention. 2

Before explaining in detail the present inven tion it is to beunderstood that the invention is not limited in its application tothedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of bein practiced or carried out in various ways. Alsoit is to be understood that the phraseology or ter- 7 showing in planthe spray gun moving chain, the observer minology employed herein is forthe purpose of description and not'of limitation, and it is not intendedto limit the invention claimed herein beyond the requirements of theprior art.

In the drawings there is shown, by way of example, a spraying machineadapted for automatic spraying of workpieces such as frames, curvedmoldings and the like. The machine is termed automatic, since the onlymanual operations in connection with operating this improved machine isloading and unloading of the workpieces on the work conveyor, all otheroperations being performed automatically by improved means performingpredetermined functions.

The machine illustrated in the drawings and hereinafter described isadapted for painting by spraying a frame molding for a motor vehiclebody, said molding being in the form of a rectangular frame with roundedcorners. It will be understood, however, that machines constructed inaccordance with the present invention may be used for painting orspraying a great number of articles of various shapes, and, in fact, themachine hereinafter described may be adapted for painting workpieces ofconfigurations different than that of the above specified frame moldingwhich may be done by changing the guiding means of the spray gun andproperly arranging the location and operation of the relay and switchmeans.

The machine illustrated in the drawings comprises generally a workconveyor adapted to receive workpieces to be painted, at one of its endsand to discharge the same at its other end. Superjacent of said conveyorthere is provided a movable spray gun adapted to be moved in a pathcorresponding to the configuration of the frame moldings to be sprayed.The work conveyor and a chain moving said gun are actuated with the aidof electric motors. There are also provided means for opening andclosing air conduits of said gun at the beginning and at the end of theoperative movement thereof around said path, for starting and shuttingofl the spray gun. The machine is provided with a plurality of switchesand relays included in an electric circuit connected to a suitablesource of electric energy and adapted to control the above mentionedelectric motors. Said switches and relays are so arranged that the workconveyor moves only until a workpiece to be sprayed reaches apredetermined position under said spray gun, whereupon the conveyormotor is shut off and the workpiece comes to rest. At this point theelectric motor actuating the gun moving chain is automatically startedand the spray gun moves around said frame, means also being provided toopen the air conduit thereby starting operation of the spray gun. Whenthe spray gun reaches the end of its working movement, the gunchainactuating motor is switched oflf, and the spray gun is shut off.Simultaneously, the work conveyor motor is switched on and the workconveyor begins moving to carry the sprayed workpiece to the dischargeend thereof and to bring the new wakpie'ce into the spraying positionunder the sway gun.

Referring to the drawings and particularly-to Figs. 1, 4 and 6, thespraying machine illustrated therein comprises a frame made up of aplurality of members forming a table having legs l5 and horizontalmembers l6. On said table there is operatively mounted an electric motorI'I connected drivingly through a gear box !8 effecting suitable speedreduction, sprocket wheel I! engaged by a chain 20 driving a secondsprocket wheel 2| with a shaft 22 on which said sprocket wheel 2| ismounted. The shaft 22 has two intermediate size sprocket wheels 23 andconstitutes a driving shaft of the work conveyor adapted to carryworkpieces past the spray gun.

The work carrying conveyor generally indicated by the numeral 24comprises two endless connectors, in the present instance chains 25,driven by the sprocket wheels 23, said chains being passed around idlersprocket wheels 26 and large size idler sprocket wheels 21. There isprovided four of such large idler sprocket wheels divided into pairs,each pair being operatively mounted on a shaft 28 having ends journalledin bearings 29 secured to the lower horizontal members 16 of the table.

To the links of the chains there are secured pieces 30 (see Fig. 5), thetwo opposing pieces of the chains 25 being connected by means of a baror rod 3|. Since links of the chain 25 are relatively small, the bars 3|are arranged relatively close together, thus forming in effect a ratherwide built-up flexible conveyor passing around the sprocket wheels anddriven by the electric motor ll. Thus, when the electric motor I1operates it rotates a sprocket wheel l9. Rotation of said wheel I9 istransmitted by the chain 20 to the second sprocket wheel 2| and theshaft 22. The sprocket wheels 23 secured on the ends of the driven shaft22 drive the chains 25 and therefore the entire conveyor.

The work conveyor 24 is adapted to receive workpieces 32 which in thepresent instance are garnish moldings such as are used in motor vehiclebodies. The moldings are of a substantially rectangular form, thuspresenting workpieces of closed linear configuration. The workpieces 32are located on said conveyor by means of suitable means such as blocks33 provided on the bars or rods 3|.

The conveyor 24 is adapted to move intermittently and to receivevworkpieces at its receiving end, bring them to the spray gun generallyindicated by the numeral 35 and to discharge said workpieces at itsdelivery end. Loading and unloading of the conveyor 24 is done by handas was explained above.

Intermittent motion of the conveyor 24 is effected by opening andclosing the electric circuit feeding the work conveyor motor l1,theopening of said circuit and consequently stopping the motor I 7 beingeffected at the moment when a workpiece reaches a predetermined positionunder the spray gun 35. In the present embodiment of the invention suchswitch is exemplified by the switching device 36 operated forperformance of the above function by a relay 3! which relay ishereinafter termed the first relay. Said first relay is operated in turnby means of a photoelectric device, often referred to in the art as anelectric eye, said device including a projector 3& fed from an electriccircuit supplying electric current brought to proper voltage andamperage with the aid of a transformer 39 connected to the electricsource, in the presentinstance the regular power line.- The projector 38is adapted to throw a beam of light passing just above the conveyor andreceived by a screen of a light sensitive device 40 operativelyconnected to said first relay 31. The beam of light is adapted to beintercepted by a workpiece when the same reaches a predeterminedposition, such interception of the light beam causing the lightsensitive device 40 to operate the first relay 3'! hose 5441, see Fig.5.

the desired rotative speed at the drive shaft 43 carrying a drive pinion'44, the rotation of which is transmitted with the aid of a chain 45 toa driven wheel 46'. The wheel 46 is secured to a shaft 4'! on'theopposite end of which is secured a driving wheel 48 engaging a gunmoving chain or conveyor 49. The gun moving chain 49 is adapted to movein a predetermined path corresponding to the configuration of theworkpiece 52 which path is determined bythe guiding means generallyindicated by the numeral 50 and comprising a built-up templet of aconfiguration substantially similar to that of the workpiece 32. a gun35 by means of an arm or link 5i adapted to move bodily with said chain49 making one complete revolution as the chain makesone complete turn.The link 5i is secured to the gun in such a way as to rotate the same assaid link moves around.

Fig. 6 illustrates various positions of the gun in the rotating movementthereof. It should be understood that the actual path of the gunalthough similar in its configuration to the configuration of i theworkpiece is considerably smaller than the workpiece. In many instancesonly rotation of the gun will be sufficient for spraying workpieces ofenclosed configurations.

The gun 35 is carried by a head generally indicated by the numeral 52,said head being a struc- The chain as is connected with As. alreadyexplained, there are provided means, which become active at the momentof stopping of the work conveyor, operating to switch onthe spray gunmotor 4|, and also to start the spray gun 35 by opening an air valve 65admitting air under pressure to said gun 35 through the air conduit 51.Said means comprise in the present embodiment of the invention a secondrelay 66 electrically connected to said light sensitive device 40, andto the power line through the switch 35a as shown in the diagram of Fig.10; When the work conveyor stops, the second relay 66 switches on thegun conveyor motor 4! and energizes the solenoid 61,

which overcomes under said conditions, the resistance of the spring 58.

On the gun moving chain d5there is provided a pin or block 69 adapted toengage a hook It operated by an electric eye solenoid H. The hook Hi isadapted to operate the. switches 36 and 36a. A spring 12 is compressedwhen the hook it is caught by the moving pin 65, and when the hook beingraised by the solenoid ii is released, said spring expands, returningthe switches 35 and 36a into the positions shown in Fig. 10. This causesswitching on of the work conveyor motor it asexplained. When, however,the solenoid ii is de-energized and the hook it is engaged by the pintil, the switches 35 and 36a are operated to stop the spray gun motor Mand the gun moving chain 45. At the end of the movement of the gunmoving chain 45, the above means operate to start the work conveyor, asalready described, thus beginning a new operative cycle.

A general switch ll-i is provided for the purpose" of starting andstopping the entire machine.

When said switch is closed the work conveyor beture providing threeconcentric conduits, 53, 53a,

and 5%, the central conduit 53 having a connection for a rubber hose 54connected to the paint supply tank 55. The paint from said conunderstoodthat the concentric conduits are formed as shown in Fig. 9 by concentrictubes connected to the gun and rotatable therewith. Although the hoselines 54, 56 and 5i are fixed against rotation with. the head 52 theyremain at all times in communication with the concentric tubes duringany rotative movement thereof in response to corresponding movements ofthe gun.

The head 52 is rotatably carried by an arm 53 hingedly connected asshown at'59 to an arm 69 hingedly secured to the post 5! secured to theplate 62. The plate 62 carries the gun actuating and guiding means, andis in turn secured to the horizontal members i6 of the table or frame ofthe machine.

gins moving. It is desirable to put a first workpiece on the conveyorwhen the same is still stationary, since if no workpieces are carried bythe conveyor, it will move continuously, but the spray gun operatingmeans will remain inactive.

Since the relays 5i and are of a conventional design, the diagram ofFig. 10 is believed to be quite sumcient for those skilled in the art toeffect proper connections of the devices combined, tracing of allcircuits under the conditions men-' tioned being deemed unnecessary.

I claim:

1. In a spraying machine, a spray gun, a work conveyor operativelyarranged with its working side in spraying proximity to said gun andadapted to move to a spraying position at said gun a workpiece of asubstantially rectangular linear configuration; guiding means adapted toguide the spray gun in a path corresponding substantially to theconfiguration of the workpiece; an electric circuit including a sourceand an electric motor adapted to actuate said work conveyor, and asecond electric motor adapted to actuate said sprayjgun in said path;means adapted to switch on said conveyor motor when said workpiecereaches its spraying position; and means for starting said spray gunmotor when said conveyor stops, and starting said conveyor motor whenthe spray gun' completes its path.

suitable construction, and being in itself a well known device it neednot be described in detail.

2. In a spraying machine, a bodily movable spray gun, a plurality of airconduits delivering air under pressure for operating said gun; a valvecontrolling said-conduits; an electrically actuated work conveyoradapted to carry workpieces past said spray gun and to bring themsuccessive- 1y into a spraying position thereat; an electricallyactuated flexible connector means for moving said gun in a pathcorresponding substantially to the configuration of said workpieces;photoelectric means controlled by the movement of the workpieces on saidwork conveyor and adapted to stop said conveyor when a workpiece reachesa predetermined spraying position with respect to said spray gun; aplurality of relays controlled by said photoelectric means and adaptedto open electromagnetically said air conduits to start saidgun when thework conveyor stops, to stop said gun moving means when the path/of thegun is completed simultaneously shutting off said gun and starting againsaid work conveyor for carrying away the sprayed workpiece and bringingup another workpiece for starting the nest operative cycle. v

In a spraying machine, a bodily movable spray gun, a plurality of airconduits delivering air under pressure to said gun for operating thesame; a valve adapted to interrupt said conduits for shutting off saidgun; a work conveyor adapted to carry workpieces past said gun and tobring them one after another into a spraying position thereat; anelectric motor adapted to actuate said i nected relays and switchescontrolled by said photoelectric means and adapted tostop said conveyormotor by opening the electric circuit thereof when said light beam isintercepted by a workpiece, to open said air conduitselectromagnetically for starting operation of the gun, and to start saidflexible connector motor by closing the electric circuit thereof formtuating said flexible connector means and moving said gun in said path.

4. In a spraying machine, a spray gun, a plurality of air conduitsdelivering air under pressure to said gun for operating the same; avalve adapted to interrupt said conduits for shutting off said gun; awork conveyor adapted to carry workpieces past said gun; an electricmotor adapted to actuate said conveyor; a flexible connector meansadapted to move said gun along a path corresponding to the configurationor the workpieces; an electric motor adapted to actuate said connector;photoelectric means including a device produc ng a light beaminterceptable by a workpiece reaching a predetermined position withrespect to said gun at the initial position thereof; relay-and-switchmeans controlled by said photoelectric means and adapted to stop saidconveyor motorwhen said light beam is intercepted by a workpiece tobring said workpiece to rest for spraying, and to start said conveyormotor after the spraying operation is completed.

5. In a spraying machine, a bodily movable spray gun, a plurality of airconduits delivering air under pressure to said gun for operating thesame; a valve adapted to interrupt said conduits for shutting on saidgun; a work conveyor adapted to carry workpieces past said gun and tobring them one after another into a spraying position thereat; anelectric motor adapted to actuate said conveyor; a flexible connectormeans adapted to move said gun along a path corresponding to theconfiguration of the workpieces; an electric motor adapted to actuatesaid connector; photoelectric means including a device producing a lightbeam interceptable' by a workpiece reaching a predetermined positionwith respect to said gun at the initial position thereof; arelay-and-switch means controlled by said photoelectric means andadapted to stop said conveyor motor by interrupting the circuit thereofwhen said light beam is intercepted by a workpiece, to open said airconduits electromagnetically for starting operation of the gun, to startsaid flexible connector motor by closing the electric circuit thereoffor actuating said flexible connector means and moving said gun in saidpath, to stop the connector motor by opening the electric circuitthereof when the gun reaches the end of said path, simultaneouslyshutting off said gun and starting said work conveyor motor by closingthe electric circuit thereof.

6. In a spraying machine having a bodily movable spray gun, means formoving said gun along a closed curvilinear path, a conveyor adapted tomove a workpiece of a closed curvilinear configuration substantiallycorresponding to that of said gun path past said-gun, an electric motoractuating said conveyor, an electric circuit including a source intowh-'ch said motor is interposed for operation, a hotoelectric daviceadapted to break said circuit and to stop said motor and, consequently,the conveyor when said pieceireaches a predetermined position near saidspray gun, thus bringing the workpiece to rest for spraying, means 7controlled by said device and adapted to move the operating gun aroundits curvilinear path thus following the periphery of said workpiece, andmeans adapted to closesaid circuit after the spraying operation iscompleted thus starting said motor for actuating the conveyor andcarrying said workpiece away from said gun.

'7. In a spraying machine, a spray gun; an electrically actuated workconveyor adapted to move a workpiece of a closed linear configuration toa spraying pi sition at said gun, means actuated by said conveyor whenthe workpiece reaches spraying position, said means being adapted tostop said conveyor and consequently said workpiece at said gun and tohold it stationary until the spraying operation is completed; guidingmeans for said gun so located with respect to the workpiece when thesame is held stationary that when the spray gun is moved along saidguiding means the spray follows substantially the configuration of theworkpiece, the configuration of said guiding means being substantiallysimilar to that of the workpiece; and an electrically actuated flexiblemem her for moving said gun along said guidin means while the workpieceis held stationary.

8. In a spraying machine, a spray gun; an

electrically actuated work conveyor adapted to move a workpiece of acurved linear configuration to a spraying position at; said gun, meansactuated by said conveyor when the workpiece pleted; guiding means forsaid gun having configuration substantially similar to the configurationof the workpiece and so located with respect to the stationary heldworkpiece that when the spray gun is moved along said guiding meansthespray follows substantially the configuration of the workpiece; anelectric circuit including a source and. an electric motor; a flexibleendless member drivingly connected to said motor and adapted to movesaid gun along said guiding means while the workpiece is heldstationary.

9. In a spraying machine, a spray gun; an electrically actuated workconveyor adapted to move a workpiece of a curved linear configuration toa spraying position at said gun, means actuated by said conveyor whenthe workpiece reaches spraying position, said means being adapted tostop said conveyor and consequently said workpiece at said gun and tohold it stationary until the spraying operation. is completed; guidingmeans for said gun having a configuration substantially similar to thatof the workpiece and so located with respect to the workpiece when thesame is held stationary and the spray gun is moved along said guidingmeans, the spray follows substantially the configuration of theworkpiece; an electric circuit normally kept open and including a sourceand an electric motor electrically interposed in said circuit, anendless chain drivingly connected to said motor and adapted to move saidgun along said guiding means; and means adapted to close said circuitwhen the workpiece reaches its spraying position, and to open saidcircuit again after said gun completes its movement along said workpieceand returns to its original position.

10. In a spraying machine, a bodily movable spraying gun, a workconveyor operatively arranged adJacent said spraying gun and adapted tomove workpieces of curvilinear. configuration to and past said gun.means adapted to hold the workpieces in predetermined positions on saidconveyor, means adapted to move said conveyor intermittently to bringthe workpieces successively to said gun, electric means adapted to stopsaid conveyor when a workpiece reaches a predetermined position nearsaid gun in order to hold the workpiece in spraying proximity to saidgun until the spraying operation is completed, valve means controlled bysaid conveyor to cause operation of said gun when the conveyor stops,and guiding means for said gun so arranged with respect to the workpieceon said conveyor in proximity to said gun that when the Spray gun ismoved along said guiding means the spray from said gun followssubstantially the configuration of said workpiece, and means for movingsaid gun along said guiding means while the workpiece is being heldstationary.

11. In a spraying machinev for spraying workpieces of uniform sizes, aspray gun bodily movable along a curvilinear path lying ina-substantially straight plane and substantially corresponding to theconfiguration of the workpiece to be sprayed, an intermittently movingendless conveyor adapted to receive workpieces and to bring them oneafter another into a position in spraying proximity to said gun andtostop in such a position having the respective workpiece in such spacedrelationship to the gun that when said gun moves along its path thespray of the gun substantially follows the configuration of saidwork-piece, means stoppin said conveyor as a workpiece reaches saidposition, and means beginning the moving of said gun for spraying saidworkpiece as said conveyor stops.

12. In a spraying machine for spraying workpieces of uniform sizes, aspray gun bodily movable along a curved closed path substantiallycorresponding to the configuration of the workpieces to be sprayed,valve means controlling the opening and closing of the spray of saidgun, an endless conveyor adapted to receive workpieces to be sprayed andto bring them successively one after another into a spraying position atsaid gun and when stopped to hold a workpiece in such position for aperiod of time suflicient for said gun to travel around its pathspraying said workpiece, an electric motor actuating said conveyor, anelectric circuit into which said motor is electrically interposed foroperation, a source of electric energy interposed in said circuit, aphotoelectric device adapted to be actuated by said conveyor when aworkpiece reaches said spraying position to break said motor .circuitand to stop said motor and said conveyor in order to hold the workpiecestationary until the spraying operation is completed, and a relay meansadapted to be controlled by said photoelectric device and to actuatesaid gun valve means when said conveyor stops,

HERBERT J. PA'I'IISON.

- CERTIFICATE OF CORRECTION i'a'tont 110. $281,169. -Apr1l 2a,- 19lrz.

HARBERT J. PATIISON.

1 11: 1: n r5y.-c.r1 1. that error u roar-o in the print a dspecification of :50" nimborad pat ent requ'iringcorrection as follows:Page hi, first coin mi ll-{cl'ujn 2} before "when"- 1-ns ert --mov1ngmeans-q and tha t tho quid Letters Paton; ohould be read with thiscorrection therein that amp my foontoz'kp t o tho' reo'ord of the casein one Patent .Otfl'ce. lgped'ondfa'oalori-thia 25 d ad or mm, A. n.1912.:

Hoary Van Aradale, (Seal) Acting comiasioner of Patents.

